A facile route to synthesize nano-MnO/C composites and their application in lithium ion batteries

Among various anode materials for lithium ion batteries, MnO has attracted a wide-spread attention for its low charge potential (1.0 V vs. Li/Li+) and high theoretical capacity (755 mAh g−1). In this paper, we propose a facile way to synthesize carbon-coated nano-MnO powders (MnO/C). Mn3O4 nanoparticles with a particle size of about 20 nm are firstly obtained in an alcoholysis process of manganese acetate tetrahydrate with diethylene glycol as the solvent. Then glucose is used as both a carbon source and a reducing agent to prepare MnO/C nanospheres. From the mixtures of Mn3O4 and glucose, nano-MnO/C composites with a carbon content up to 18.1 wt% are obtained. X-ray diffraction and transmission electron microscopy are used to analyze the structures of the nano-Mn3O4 and nano-MnO/C composites. The electrochemical properties of the nano-MnO/C composites are also characterized. The electrode made from 10.7 wt%-carbon-coated MnO/C shows very stable cycling performance with a high reversible capacity of 939.3 mA h g−1 after 30 cycles at 0.1 C. This electrode also shows favorable rate performance with specific capacities of 726.7, 686.8, 633.0 and 587.9 mAh g−1 at 1 C, 2 C, 5 C and 10 C, respectively.

► A relatively simple alcoholysis to prepare nano-Mn3O4. ► A facile carbothermal reduction process to obtain nano-MnO/C composite. ► Nano-MnO/C anode showing outstanding cycling and rate performances.